- Certainly, fetal liver length (FLL) increases with gestational age, and understanding its standard deviation (SD) is crucial for assessing normal growth patterns. Based on the study by Tongprasert et al., the relationship between FLL and gestational age (GA) from 14 to 40 weeks can be modeled using the following equations:
- Mean FLL (mm): Mean = 1.61 × GA − 6.75
- Standard Deviation (SD): SD = 0.15 × GA − 1.5
Nots: The 5th and 95th percentiles are calculated as Mean ± 1.28 × SD, assuming a normal distribution.
Fetal Liver Length by Gestational Age (Weeks)
| Gestational Age (weeks) | Mean FLL (mm) | SD (mm) | 5th Percentile (mm) | 95th Percentile (mm) |
|---|---|---|---|---|
| 14 | 15.79 | 0.60 | 14.61 | 16.97 |
| 16 | 18.99 | 0.90 | 17.52 | 20.46 |
| 18 | 22.21 | 1.20 | 20.23 | 24.19 |
| 20 | 25.41 | 1.50 | 22.91 | 27.91 |
| 22 | 28.63 | 1.80 | 25.65 | 31.61 |
| 24 | 31.83 | 2.10 | 28.38 | 35.28 |
| 26 | 35.05 | 2.40 | 31.11 | 38.99 |
| 28 | 38.25 | 2.70 | 33.84 | 42.66 |
| 30 | 41.47 | 3.00 | 36.57 | 46.37 |
| 32 | 44.67 | 3.30 | 39.30 | 50.04 |
| 34 | 47.89 | 3.60 | 42.03 | 53.75 |
| 36 | 51.09 | 3.90 | 44.76 | 57.42 |
| 38 | 54.31 | 4.20 | 47.49 | 61.13 |
| 40 | 57.51 | 4.50 | 50.22 | 64.80 |
Neoneatal Midclavicular Liver Length by Age (Months)
| Age (Months) | Mean Liver Length (cm) | Standard Deviation (cm) |
|---|---|---|
| 0 (Newborn) | 5.9 | ±0.8 |
| 1 | 7.6 | ±1.18 |
| 2 | 7.8 | ±1.20 |
| 3 | 8.0 | ±1.22 |
| 4 | 8.2 | ±1.24 |
| 5 | 8.4 | ±1.26 |
| 6 | 8.6 | ±1.28 |
| 7 | 8.8 | ±1.30 |
| 8 | 9.0 | ±1.32 |
| 9 | 9.2 | ±1.34 |
| 10 | 9.4 | ±1.36 |
| 11 | 9.6 | ±1.38 |
| 12 | 9.8 | ±1.40 |
Nots: These values represent average measurements; individual variations can occur. Liver size correlates strongly with body height and weight, so these factors should also be considered during assessment.
Normal Midclavicular Liver Length by Age (1–80 Years)
| Age Range (Years) | Mean Liver Length (cm) | Standard Deviation (cm) | Normal Range (cm) |
|---|---|---|---|
| 1–2.5 | 8.5 | ±1.0 | 6.5–10.5 |
| 3–5 | 8.6 | ±1.2 | 6.5–11.5 |
| 5–7 | 10.0 | ±1.4 | 7.0–12.5 |
| 7–9 | 10.5 | ±1.1 | 7.5–13.0 |
| 9–11 | 10.5 | ±1.2 | 7.5–13.5 |
| 11–13 | 11.5 | ±1.4 | 8.5–14.0 |
| 13–15 | 11.8 | ±1.5 | 8.5–14.0 |
| 15–17 | 12.1 | ±1.2 | 9.5–14.5 |
| 18–25 | 13.6 | ±1.7 | 11.9–15.3 |
| 26–35 | 13.7 | ±1.7 | 12.0–15.4 |
| 36–45 | 14.0 | ±1.7 | 12.3–15.7 |
| 46–55 | 14.2 | ±1.7 | 12.5–15.9 |
| 56–65 | 14.4 | ±1.7 | 12.7–16.1 |
| >66 | 14.1 | ±1.7 | 12.4–15.8 |
The caudate lobe of the liver, located posteriorly between the inferior vena cava and the ligamentum venosum, can be evaluated using ultrasound to measure its anteroposterior (AP) diameter. While specific normative data for the caudate lobe's AP diameter across different age groups is limited, general reference values have been established in adult populations.
- A C/RL ratio < 0.6 is considered normal.
- A C/RL ratio > 0.65 suggests a high likelihood of cirrhosis.
| Age Group | Normal Caudate Lobe AP Diameter |
|---|---|
| Newborns and Infants (0–2 years) | 15–20 mm |
| Children (3–10 years) | 15–30 mm |
| Adolescents (13–18+ years) | 20–40 mm |
| Adults (18+ years) | Up to 30 mm |
These measurements are approximate and can vary based on individual anatomy and body size. It's important to interpret these values in the context of the patient's overall clinical picture and in comparison with other liver measurements. For instance, an increased caudate lobe size relative to the right lobe may suggest certain liver pathologies, such as-
- Detect hepatomegaly
- Monitor chronic liver diseases
- Assess congenital or structural abnormalities
| Age Group | Normal Left Lobe AP Diameter |
|---|---|
| Newborns (0–1 month) | 20–30 mm |
| Infants (1 month–2 years) | 25–40 mm |
| Young Children (3–5 years) | 30–50 mm |
| Children (6–10 years) | 35–60 mm |
| Adolescents (11–17 years) | 40–70 mm |
| Adults (18+ years) | Up to 70 mm (7 cm) |
These values are approximate. Use body surface area (BSA) or height-based nomograms for more precise pediatric assessments.
Liver volume (cm3) =343.71 + (0.84 × ABC) where ABC is the product of the three linear measurements.
Fetal Liver Volume by Gestational Age
| Gestational Age (Weeks) | Mean Liver Volume (mL) |
|---|---|
| 20 | 8 |
| 24 | 18 |
| 28 | 36 |
| 32 | 62 |
| 36 | 94 |
| 40 | 120 |
Liver Volume by Age Group
Liver Volume by Age Group (Approximate Values)
| Age Group | Liver Volume (mL) | Notes |
|---|---|---|
| Newborn | 120–250 mL (mean ~185 mL) | Volume varies by birth weight and length |
| 1 year | ~700–800 mL (mean ~750 mL) | Rapid growth; ~half of adult liver volume |
| 5 years | ~850–1050 mL (mean ~950 mL) | Liver volume increases with body size |
| 10 years | ~1000–1200 mL (mean ~1100 mL) | Close to adult female liver volume |
| Adolescents (11–17) | ~1300–1800 mL (mean ~1550 mL) | Growth continues; depends on height and weight |
| Adult Female (18–65) | ~1200–1400 mL (mean ~1300 mL) | Relatively stable |
| Adult Male (18–65) | ~1400–1800 mL (mean ~1600 mL) | Typically larger due to body mass |
| Older Adults (65+) | ~1200–1500 mL (mean ~1400 mL) | Slight decline (~100–200 mL) due to age-related liver shrinkage |
Normal size of the right lobe compared to the right kidney.
Enlarged right liver lobe with subtle increase in echogenicity compared to the cortex of the right kidney.
The right liver lobe is smaller and has rounded margins and an irregular outline, in keeping with fibrotic retraction
C/RL Ratio Formula
\( \text{C/RL Ratio} = \frac{\text{Caudate Lobe Width}}{\text{Right Lobe Width}} \)
- Caudate Lobe Width:Measured from the medial edge of the caudate lobe to the right border of the inferior vena cava.
- Right Lobe Width:Measured from the right lateral margin of the liver to the right edge of the middle hepatic vein (or portal vein bifurcation, depending on method).
- C/RL < 0.6 → Normal
- C/RL ratio > 0.65 → Suggestive of cirrhosis
- Some sources use > 0.7 as a more specific cutoff
⚠️ These measurements are best made using cross-sectional imaging like CT or MRI. Ultrasound can be used but is more operator-dependent.
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